This invention relates to a method for jointing a plurality of overlapping plate materials to one another and an apparatus used to effect such method.
In jointing or coupling a plurality of overlapping plate materials to one another, there have hitherto been used rivets, combinations of bolts and nuts, or welding. When using the rivets or the combinations of bolts and nuts, it is necessary to perform riveting or bolt-nut mating after forming through holes for the rivets or bolts in the plate materials. This means that the jointing requires a lot of time, comparatively. Further, the formation of the through holes will reduce the mechanical strength of the plate materials. If the plate materials are covered with a thin film such as a coating film, moreover, the film will be damaged at the peripheral edge portions of the through holes. If the film is a coating film, the plate materials will rust, starting from the damaged portions of the film. The kinds of plate materials which can be joined together by welding are limited. Further, the welding method requires a special equipment which uses gas or high-voltage current.
The object of this invention is to provide a method for jointing plate materials capable of reducing the time required for joining without reducing the mechanical strength of the plate materials or damaging films on the materials and without limiting the kinds of applicable materials or requiring any special equipment, neither, and an apparatus therefor.